<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
<h2>Nap chong toan tu</h2>
nghia la co 1 class A
A a, b;
a = a + b; // ghi de toan tu + vi du lop phan so de nhin cho no tu nhien

toan tu is
   o is Fraction // tuong duong voi instanof trong java

</body>
</html>